Hyper Sports: is there a self-test? Who generates /reset?

MajorHavoc

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Hyper Sports: is there a self-test? Who generates /reset?

Attempting to resurrect a HS board. Have the service manual and two page schematics off the web.

1) Is there a self-test? If so, how do I activate it?
2) I am trying to find who generates reset on the board. Back tracing the signal from the Z80 CPU has only gotten me to signal inputs. Obviously I missed something, but what?

Thanks!
 
Perhaps the fact tht schematics for this board are available on arcarc.

Mark,

Thanks for the reply. I guess you missed (or ignored) the part of my post where I mentioned that I have the online version of the schematics and user manual.

Unfortunately the schematics are not easy to read and the /reset signal just hangs off in space and I have yet to find where it connects to.

Also, I have back-traced the signal on the board 2 or 3 times already following the only path I could find and have always ended up at a pin that is an input. I guess I just need to keep repeating the process, eh?

Thanks again!
 
/RESET comes from pin 3 of the LS244 at B2
check the bottom left on page "2 of 2" the schematics

The 555 timer on the top board generates the master /RES which is used to generate /RESET.
/RESET goes high once /RES goes high and custom 504 on the lower-board at D1 outputs a high on pin 4.

See the middle-left of page "1 of 2", it's the output of G2 LS08, the output is helpfully unlabeled.

- James
 
Thanks James. That was helpful!


/RESET comes from pin 3 of the LS244 at B2
check the bottom left on page "2 of 2" the schematics

The 555 timer on the top board generates the master /RES which is used to generate /RESET.
/RESET goes high once /RES goes high and custom 504 on the lower-board at D1 outputs a high on pin 4.

See the middle-left of page "1 of 2", it's the output of G2 LS08, the output is helpfully unlabeled.

- James
 
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